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1.
Different thickness of barrier-type oxide film was intentionally grown on the Al metal surface and the effect of barrier film on the formation of nanoporous aluminum oxide film during anodization was investigated to control the nanopore structure. Analysis of potential transients during anodization indicated that anodic oxide film is initially overlaid on the barrier film but the anodic film is more facile to dissolve than barrier film. As the thickness of barrier film increases, both nanopore diameter and density decrease but the pore length is irrespective of barrier-film thickness.  相似文献   

2.
电影影片档案是一个国家极为珍贵的档案,主要分为两类,第一类是电影原始素材,即电影原底片和中间片,第二类是电影拷贝片,为电影标准拷贝片。我国电影原始素材资料档案库位于西安,而电影拷贝档案库则建在北京。本全面探讨了电影资料档案保存方面的一些重要技术问题,如:电影影片档案保存环境的国际标准,易燃易爆的硝酸纤维片基胶片的保存,三醋酸纤维片基在影片保存期间的醋酸综合症问题.外借的电影档案影片保存环境不佳和长期不还所造成的损害问题等等。  相似文献   

3.
5A06铝合金阳极氧化和微弧氧化膜绝缘性能研究   总被引:2,自引:0,他引:2  
采用阳极氧化和微弧氧化方法对5A06铝合金进行表面绝缘化处理,并对试样膜层的形貌、物相、绝缘电阻、漏电流、击穿电压和抗液氮冲击等性能进行了研究.结果表明,5A06阳极氧化膜为非晶相,而微弧氧化膜主要为晶相γ-Al2O3.无论是阳极氧化膜还是微弧氧化膜,干燥条件下的交流和直流击穿电压均较潮湿条件下的高;相同电流模式下,氧...  相似文献   

4.
为了研究一步法黑色磷化膜的生长过程,测试了钢铁基体在黑色磷化液中的循环伏安曲线及时间电位曲线,利用扫描电镜观察了膜的生长过程及不同温度条件下膜层形貌,分析了膜重随时间的变化,对成膜机理进行了探讨.研究表明:在适宜的磷化时间及磷化温度下,黑色磷化膜晶体数量多,尺寸适中,孔隙小,膜层致密,均匀,厚度适中,色泽乌黑,采用一步法制备黑色磷化膜,可减少生产工序,降低成本,所得膜层性能优异.在适宜的磷化时间内,黑色磷化膜的平均膜重为52.7 g/m2,在磷化膜中生成氧化铜从而使磷化膜成黑色.  相似文献   

5.
报道了薄膜润滑的本质以及它与弹流润滑和边界润滑间关系的研究结果。根据各种特性膜厚度的变化分析了各润滑状态之间的转化关系,提出了润滑状态与宏观摩擦副所处状态关联与区分准则。  相似文献   

6.
特种包装薄膜对青椒保鲜效果的探讨   总被引:3,自引:1,他引:2  
以普通PE包装薄膜为对照,探讨了淀粉膜、篮光膜、PVA膜三种特种薄膜对青椒保鲜效果,表明,淀粉膜、蓝光膜较PE膜更有利于青椒保鲜,而PVA膜较PE膜不利于青椒保鲜。  相似文献   

7.
孙权  鹿业波  徐晓斌  施正浩 《包装工程》2019,40(21):222-227
目的为了可靠地检测薄膜电池封装膜弯曲疲劳寿命,设计并制备一台封装膜弯曲疲劳寿命检测仪。方法仪器主要由机械运动机构、运动控制系统、固定保护机构等组成,使用此仪器对薄膜电池封装膜进行试验,研究循环弯曲对其的影响;利用有限元仿真,分析薄膜电池弯曲时封装膜内部的应力变化情况。结果随着弯曲角度的增大,封装膜所受的弯曲应力不断增大;在弯曲循环测试中,随着循环次数的增加,封装膜表面会产生疲劳裂纹,破坏了透明电极的胶合状态,影响了电池的光电性能;获得了封装膜在不同弯曲角度下的疲劳寿命曲线。结论该检测仪操作方便,基于此仪器进行弯曲疲劳寿命检测可有效提高薄膜电池封装的可靠性。  相似文献   

8.
Abstract

The Light-Section Microscope measures the thickness and surface roughness of transparent film coats without contacting them. It enables the determination of tablet film coat thickness at different regions on a tablet surface and analysis of coat thickness variation. Examination of aqueous film coated tablets using a Light-Section Microscope has shown that the coat application conditions can influence the film density and thickness, film thickness variation and film coat surface roughness. Coat application conditions which give rise to smoother surfaces are shown to produce more dense, thinner coats which may exhibit a more even thickness on smooth substrates but larger variations in film thickness on rough substrates. The potential for film thickness and surface roughness to vary at different positions on the substrate surface has also been demonstrated, with film coats tending to be smoother and thinner at the periphery of tablet faces.  相似文献   

9.
A carbon film was produced from polyphenylene (PP) film prepared by electrochemical polymerization of benzene to obtain a uniform and thin film. The PP film (~10μm thick) was transformed into the carbon or graphite film without drastic changes of shape or size. The electrical conductivity of the film was remarkably enhanced by heat-treatment between 600 and 800° C, but further increase in the conductivity was not observed by treating at higher temperatures. This behaviour is considered to correlate with a poor degree of graphitization of the PP film. The carbonization and graphitization mechanisms of the film are discussed in connection with the structure of polyphenylene in the film.  相似文献   

10.
聚乙烯/硅橡胶共混膜的制备及其透气性能   总被引:2,自引:0,他引:2  
为了提高聚乙烯薄膜的透气性能,采用挤出吹塑的方法制备了硅橡胶(聚二甲基硅氧烷,PDMS)含量为1%~5%的聚乙烯(PE)/硅橡胶共混薄膜,用扫描电镜研究了硅橡胶在聚乙烯中的分布,测试了共混膜的透气性能。结果表明,由于吹膜过程中的拉伸作用,硅橡胶颗粒呈细长型分布于聚乙烯基体中,硅橡胶的加入并不能明显改善聚乙烯的透气性能。...  相似文献   

11.
目的 制备花青素明胶/聚乙烯醇淀粉双层复合膜,以期提高花青素单层膜的综合性能.方法 采用流延法分别制备紫薯、紫甘蓝、黑米、黑枸杞、玫瑰、玫瑰茄等6种花青素明胶/聚乙烯醇淀粉双层复合膜,并对比研究膜层的微观组织结构、含水率、力学性能及光学性能.结果 从红外光谱图中可以看出,双层复合膜分子结构没有出现新的特征峰,双层膜结合方式为物理结合,没有新的结构生成,且除紫甘蓝明胶/聚乙烯醇淀粉双层复合膜外,其余复合膜均存在明显的分层界线,2层结合处膜层结构均匀致密,结合良好.不同双层膜的含水率差异显著,而双层复合膜比花青素单层膜的含水率明显降低,不同双层膜的拉伸强度和断裂伸长率差异不显著,与单层花青素明胶复合膜相比,双层复合膜的拉伸强度和断裂伸长率大幅增加,其中紫薯双层膜的拉伸强度增加了75%,断裂伸长率增加了22.9%;所有双层复合膜的透光率相差不大,均在80%以上;与花青素明胶单层膜相比,双层膜的雾度增加了20%左右.结论 制备的双层膜改善了单层膜的力学性能,提高了花青素明胶单层膜的综合性能.  相似文献   

12.
激光诱导荧光(LIF)技术是目前较为有效的海面溢油探测技术之一,然而基于该技术的油膜厚度反演算法目前仅适用于薄油膜(≤20μm)。鉴于此,建立了一种基于LIF技术利用油膜荧光信号评估较厚油膜厚度的双波段比值模型,利用油膜荧光光谱的波形特性反演油膜厚度并论证了该算法的适用范围。实验数据得出,当油膜较薄时反演结果误差较大,随着油膜厚度增加误差逐渐降低,当油膜荧光信号趋于饱和时,误差较大且随油膜厚度的增加而快速变大。实验结果表明,该算法可以有效评估200~1400μm范围内的海面溢油油膜的厚度,并可以利用油膜荧光信号的测量相对误差评估该算法的适用范围。  相似文献   

13.
Barrier-type film growth on the high strength aluminium alloy FVS0812 has been studied by a combination of transmission electron microscopy and Rutherford backscattering spectroscopy. The film is composed mainly of amorphous anodic alumina, but is contaminated with iron species incorporated into the film from the alloy. The film may also be contaminated with silicon and vanadium species at levels below the detection limit of the present experiments. The contaminant species are primarily incorporated locally into the film during oxidation of Al13(Fe, V)3Si dispersoids and the resulting film material is of reduced resistivity compared with anodic alumina of high purity. As a consequence of the presence of regions of film material of differing resistivities, the film is of irregular thickness. The average thickness corresponds to a nm/V ratio of about 1.3. Iron species incorporated into the film migrate outwards at roughly 2.1 times the rate of Al3+ ions. The iron species are not ejected in significant amounts to the electrolyte on reaching the film/electrolyte interface and hence, a thin layer of film material highly enriched in iron species develops at the film surface. The layer may also be enriched in vanadium species, if these are incorporated into the film and migrate more rapidly than Al3+ ions. Enrichment of iron, and possibly other alloying element atoms, is found in a thin layer of alloy immediately beneath the anodic film, paralleling enrichments of alloying element atoms found following anodic oxidation of other aluminium alloys. The enrichments at both the alloy/film and film/electrolyte interfaces do not appear to be continuous across the macroscopic surface of the specimens, probably due to the non-uniformity of film growth on the two-phase substrate. The maximum voltage for the selected conditions of anodizing was limited to 68 V as a result of oxygen generation at flaws which are present extensively in the anodic film. This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   

14.
采用脉冲电晕对非极性的食品包装薄膜聚乙烯(PE)和聚丙烯(PP)进行表面处理,研究了电晕处理时的4 种因素(即放电功率、电极与薄膜间的距离、走膜速率和导辊温度)对薄膜透气率的影响,探讨了电晕处理后薄膜的透气率和薄膜的表面张力值之间的关系,建立了电晕处理对薄膜透气率的影响规律。结果表明,电晕处理对薄膜的表面张力和薄膜的透气率有明显的影响,为建立电晕处理与薄膜透气率之间的数学模型和气调包装设计提供了可靠的薄膜透气率数值计算。  相似文献   

15.
The aim of this paper was to address the effect of the residual stresses within the brittle film on the substrate on the film strength, fracture energy, and interfacial shear strength (IFSS). Special analyses were performed on the SiOx film/polyethulene terephthalate substrate systems. The residual stresses were evaluated by using the curvature method. The film strength, fracture energy, and IFSS were estimated on the basis of the multiple cracking analyses. In the multiple cracking analyses, the system was subjected to the combination of the residual stresses and the unidirectionally applied stress. Results showed that the relationship between the crack density in the film and the applied strain can be predicted by adopting the energy criterion on the basis of the knowledge on the residual stress distributions in the film segment. The film strength and fracture energy for the initiation of film cracking were almost proportional to the compressive residual stresses in the film. With increasing the compressive residual stresses within the film, the IFSS also increased.  相似文献   

16.
A novel type of high performance ultraviolet (UV) photodetector (PD) based on a ZnO film has been prepared by incorporating a BiOCl nanostructure into the film. The responsivity of the BiOCl/ZnO hybrid film PD in UV region can reach 182.87 mA W?1, which is about 2.72 and 6.87 times for that of TiO2/ZnO hybrid film PD and pure ZnO film PD. The rise/decay time of BiOCl/ZnO hybrid film PD is 25.83/11.25 s, which is much shorter than that of TiO2/ZnO hybrid film PD (51.94/26.05 s) and pure ZnO film PD (69.34/>120 s). The BiOCl nanostructure can inject photogenerated electrons into the ZnO film under UV light illumination, leading to the increase of photocurrent, and forms barriers to block the straight transmission of electrons between electrodes, resulting in the decrease of decay time. The results of control experiment show that the transfer path of photogenerated electrons formed by p–n junction will be cut off after depositing gold nanoparticles on the film surface, which means this hybrid film is a unique and novel structure to improve the optoelectronic performance of photodetectors. This novel BiOCl/ZnO hybrid structure paves new route for the development of film PDs based on ZnO film.  相似文献   

17.
Absorption spectra of gold nanoisland thin film and the composite film of gold having thin coating of Methylene Blue and Rh6G dyes have been studied. Thin gold nanoisland film shows surface plasmon resonance (SPR) peak in the visible wavelength range, which shifts to near infrared with an increase in the thickness of the film. It was found that thin film of gold consists of nanoparticles of different size and shape, particularly nanorods of noncylindrical shapes. A linear relation was found between SPR peak wavelength and the aspect ratio of the nanoparticles in gold thin film. Effective medium refractive index of the gold film is estimated to be ~2.5, which decreases with an increase in film thickness. The coating of dyes on gold films splits the SPR peak with an enhanced absorption. Enhancement in absorption of composite film is maximal when the dye absorption peak coincides with the SPR peak; otherwise enhancement in transmission is observed for all the wavelength range. Absorption amplitude of composite film peaks increase with an increase in the gold film thickness, which tend toward saturation for film thickness of ≥6 nm. A correlation shows that absorption spectra can be described by the Maxwell Garnett theory, when the gold nanoparticles have a nearly spherical shape for very thin film (≤6 nm).  相似文献   

18.
Antireflective films require an accurate film thickness to be able to perform optimally. The ideal thickness on most films is a quarter wavelength optical thickness (QWOT). The physical thickness of the QWOT film depends on the refractive index of the material that is being used. Each layer of the antireflective coating will have different optimal conditions for applying the film. When using the dip coating method, these conditions are withdrawal speed and concentration of solution.When using the currently accepted equations derived by Yang et al. to calculate the film thickness an error of 31.7% was noted when compared with the experimentally measured film thickness. Realising that the refractive index of the film plays a role in determining the thickness of the film, the equations were modified to take refractive index into account. Once this was taken into account, the calculated film thickness deviated from the measured film thickness by 8.7%. This error can be attributed to experimental errors which involve temperature and concentration fluctuations.  相似文献   

19.
油膜厚度是对海面溢油污染定量分析的一个重要指标。结合海面溢油平坦和非平坦两种厚油膜区域的形态特点,依据激光诱导荧光(LIF)技术探测不同厚度油膜的信号特征给出判定,提出平坦厚油膜区域边缘厚度评估方法,根据油膜区域边缘厚度的不同,采用荧光强度估算油膜厚度。实验观察平坦厚油膜边缘的厚度变化,利用LIF实验系统对平坦厚油膜的边缘厚度进行评估,结果表明,该方法对于厚度大于20μm的油膜厚度评估,相对偏差在±10%左右。  相似文献   

20.
研究了真空热蒸发制备CdTe薄膜的光电性能以及微结构、化学组成和成膜机理。通过X射线衍射、透射电镜电子衍射、X光电子能谱和光、暗电导测试等分析手段,系统表述了薄膜的组成、结构、表面氧化与真空热蒸发工艺的关系。指出基板温度是决定CdTe薄膜组成和结构的关键参数,150℃左右制备的CdTe薄膜具有最佳光电性能和成膜质量。另外,对CdTe薄膜的氧化机制和成膜机理也进行了初步探讨。  相似文献   

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